Background The zoledronate is a bisphosphonate widely used in the treatment of bone pathologies such as the Paget's disease and the osteoporosis, due to its convenient dosage (annual infusion), its rate of therapeutic compliance and its excellent safety profile.
Objectives Our objective in this study is to describe the clinical and demographic features of the patients treated with zoledronate in our hospital over the past five years, according to the different therapeutic indications.
Methods This is a retrospective observational study that has included 186 patients treated with zoledronate at the University Health Care Complex of Leon since January 1st, 2011 to December 31st, 2015. Two of the main therapeutic indications of the drug have included in the study: osteoporosis and Paget's disease of bone. Clinical and analytical data have been obtained from the information reported in the medical record.
Results 186 patients were included, 76.9% female and 23.1% male, with a mean age at the moment of the first infusion of 73,77±10,451 |43–97|. Forty-six of the treatments were indicated for active Paget's disease of bone (26.3%), 136 for osteoporosis (76.1%) and one for osteogenesis imperfecta.
Among the patients treated for Paget's disease of bone, 51% were male and 49% female, presenting the 48% of them monostotic fibrous dysplasia and the 52% of them polyostotic fibrous dysplasia. The mean Alkaline Phosphatase levels (ALP) at baseline was 444.82±292.85 IU/L, receiving an average dose of infusions of 1.12 with SD 0.389. The ALP levels after the infusion of zoledronate decreased to an average value of 91.98±41.94 IU/L within a year. Two of the patients needed reinfusion 4 years after the first infusion. 2% of them had flu-like symptoms and only one patient had post-infusion pathological fracture as complication.
In the group treated for osteoporosis, 18 patients were men and 118 women. 59.1% of the patients required infusion due to abnormal DXA results with -2.5 SD or less, 31.4% of the patients required it due to previous fractures and 7% due to a concomitant use of high dosage of oral steroids (prednisone>10mg/day). The mean dose of infusion in these patients was 2,63±1,38 with a mean bone mass density at the beginning of the treatment of 0,804±0,116 in the lumbar spine and of 0,73±0,128gr/cm2 in the hip. The mean bone mass density after 2 years of treatment was of 0,831±0,114 in the lumbar spine and of 0,767±0,141 in the hip.
54.8% of all patients included in the study had not received prior treatment with oral bisphosphonates, while the remaining 45.2% did receive it (33.3% for <5 years and 11.8% for>5 years).
7 patients had side effects after infusion: 4 mild adverse reactions and 2 severe reactions. Therefore, these patients required the discontinuation of the treatment due to uncomplicated osteonecrosis of the jaw and due to severe hypocalcaemia. Other causes for suspension of treatment were post-infusion fractures in the 2.2% of the cases and no improvement of bone mass density according to the DXA in the 1.1% of the patients.
Conclusions Zoledronic acid has been shown to improve the levels of ALP in the Paget's disease with a single dose, and in the bone mineral density of both the lumbar spine and the hip, presenting few complications and being a good therapeutic option.
Disclosure of Interest None declared